Publications by authors named "Meida Chen"

Regulating the chemical environment of materials to optimize their electronic structure, leading to the optimal adsorption energies of intermediates, is of paramount importance to improving the performance of electrocatalysts, yet remains an immense challenge. Herein, we design a harmonious axial-coordination Pt Fe/FeNCCl catalyst that integrates a structurally ordered PtFe intermetallic with an orbital electron-delocalization FeNCCl support for synergistically efficient oxygen reduction catalysis. The obtained PtFe/FeNCCl with a favorable atomic arrangement and surface composition exhibits enhanced oxygen reduction reaction (ORR) intrinsic activity and durability, achieving a mass activity (MA) and specific activity (SA) of 1.

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Crystal structure engineering in nanoparticles has been regarded as a vital method in catalyst development and design. Herein, PtFe nanocubes, manufactured with ordered PtFe intermetallic structure and a desired facet of {202}, have been successfully prepared via the combination of selective deposition strategy and spatial barrier effect. In-situ X-ray photoelectron spectroscopy found that the growth of the high-index facet and formation of the nanocube for o-PtFe-202 materials arise from the surface Fe modification stabilized effect and the selective deposition of Cl, respectively.

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In order to explore the release rule of floral volatile substances and the diurnal variation of different flower development stages of 'Fengdan' in potted and ground-planted conditions, dynamic headspace adsorption combined with gas chromatography-mass spectrometry(GC-MS) was used to analyze the dynamic changes in floral volatile components and contents. Quantitative real-time PCR (qRT-PCR) was used to analyze changes in flower fragrance-regulating genes , , and at different flower development stages and a daily change process at the full-blooming stage. The results show that there were differences in aroma components and contents of 'Fengdan' at different flower development stages and different time quantum of every day.

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The designs of efficient and inexpensive Pt-based catalysts for methanol oxidation reaction (MOR) are essential to boost the commercialization of direct methanol fuel cells. Here, the highly catalytic performance PtFe alloys supported on multiwalled carbon nanotubes (MWCNTs) decorating nitrogen-doped carbon (NC) have been successfully prepared via co-engineering of the surface composition and electronic structure. The Pt Fe @NC/MWCNTs catalyst with moderate Fe feeding content (0.

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A rapid multi-element analysis method for clay mineral samples was described. This method utilized a polarized wave-length dispersive X-ray fluorescence spectrometer--Axios PW4400, which had a maximum tube power of 4 000 watts. The method was developed for the determination of As, Mn, Co, Cu, Cr, Dy, Ga, Mo, P, Pb, Rb, S, Sr, Ni, ,Cs, Ta, Th, Ti, U, V, Y, Zn, Zr, MgO, K2O, Na2O, CaO, Fe2O3, Al2O3, SiO2 and so on.

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